Many office buildings and institutional structures, such as hospitals, nursing homes, schools, and the like, install impact-protecting wall guards along corridor walls, to protect against accidental impact from wheeled carts, wheelchairs and the like. A common form of such wall guard includes a retainer element, typically an aluminum extrusion, which is mounted on the wall to be protected, at an appropriate level. A cover shell, typically of extruded xe2x80x9crigidxe2x80x9d plastic, is designed to be snapped over the previously installed retainer and provides a resilient impact cushion to protect the wall structure. Frequently, particularly for wider sizes of wall guards, one or more resilient strips are mounted on the retainer, underlying the cover shell, to provide additional support against impact deflection of the center portion of the plastic shell. The present invention improves upon existing designs of wall guards of this general type.
For some applications, it is not necessary that the retainer be a continuous extrusion. It is acceptable, in many cases, that relatively short retainer sections be fixed to the wall, spaced apart a predetermined distance, such as sixteen inches. Typically, such retainer sections are formed by extruding a continuous length of retainer cross section, cutting individual short sections from the continuous length, and drilling or otherwise machining those short, cut-off sections to provide means for mounting them on a wall structure. Pursuant to the invention, a novel and improved form of attachment clip is provided, for securing impact-resisting wall guards to wall structures in a more convenient and economical manner. The attachment clip is formed by injection molding techniques, rather than cutting of an extruded section. This enables a number of important features to be incorporated into the attachment clip to improve its functioning and also to facilitate and expedite installation of the wall guard on the wall structure to be protected.
In a preferred form of the invention, the attachment clip includes a novel form of impact-resisting spring element which is rotatably or flexibly attached at one end to the body of the clip, and slidably supported at its other end on the body of the clip. Portions of the impact-resisting element between the ends thereof project outward and serve as an impact-resisting support for a plastic cover shell attached to the surface of a wall by means of the clips.
Pursuant to one aspect of the invention, the molded clip body is formed with a hinge socket, preferably in the form of a partial cylinder of slightly more than 180 degrees. This hinge socket is offset toward one end of the clip body, and its open side faces toward the opposite end. A resilient impact-resisting element is formed with a cylindrical bead on at least one end thereof, which has a snap-fit with the cylindrical hinge socket. When the bead is snapped in place into the hinge socket, the impact-resisting element is retained against other than intentional removal. The impact-resisting element spans the center portion of the clip body, and is configured so its center portion is offset outward from the clip body so as to closely underlie a plastic cover shell mounted by means of the clip. Advantageously, the free end of the impact-resisting element is positioned over a support surface provided by the clip base, such that the free end is supported for limited sliding movement when the element is deflected inwardly under impact forces.
To facilitate accurate mounting of the clips, the molded clip bodies advantageously are provided with reference pointers, preferably in the center thereof, which can be accurately aligned with a chalk line, for example, enabling an installer to quickly install a plurality of the mounting clips along the surface of a wall structure while maintaining a high level of alignment accuracy.
In accordance with another aspect of the invention, the molded clip bodies are provided with spaced-apart pairs of locating tabs projecting from each side thereof. These are used to great advantage to facilitate accurate location and mounting of end caps that are installed to close the open ends of the extruded cover shell. Careful positioning of these ends caps is important to providing a neat overall appearance to the installation, and the provision of the locating tabs reliably assures efficient and accurate positioning of such end caps.
In a preferred embodiment of the invention, a rigid support rib underlies the center portion of the impact-resisting element. In the case of excessive impact forces, this element can serve as a distortion limit for the impact-resisting element. Additionally, this element provides means for mounting of a continuous resilient cushioning element, running the entire length of the plastic cover shell. The cushioning element, in such cases, normally would be used in place of the previously described impact-resisting spring element otherwise provided on each clip. In the alternative arrangement, the resilient cushion is mounted on a plurality of the clip bodies and spans the space between such clip bodies to provide a form of continuous cushioning along the entire length of the cover shell.
For a more complete understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of preferred embodiments thereof, and to the accompanying drawings.